1. Technical Field
The present disclosure relates to accessory lighting for vehicles and, more particularly, to a system for illuminating a user-selected pattern on a vehicle light display that automatically switches from a user-selected color or colors to a government approved color scheme when the vehicle's engine is turned on.
2. Description of the Related Art
The durability, brightness, small size, and low current draw make light-emitting diodes (LEDs) useful for motor vehicle applications beyond the required exterior motor vehicle lighting. However, governmental regulators such as the U.S. Department of Transportation (D.O.T.) limit the colors of exterior vehicle lights that may be illuminated when the vehicle is operated on the highways in order to enhance highway safety. The D.O.T. generally prohibits the use of colors other than red, amber, or white while a vehicle is operated on a road so operators of other vehicles (such as automobiles, motorcycles, tractor-trailer combinations, motor homes, etc.) do not mistake the vehicle for an emergency vehicle. In addition, the D.O.T. regulates the colors of lights on vehicles to ensure consistency of light colors on vehicles so that operators can determine the orientation of a vehicle by the color of light the operator is viewing. Vehicle lighting colors are limited by the D.O.T. based on the location of the lights on the vehicle and a direction the lights are facing. The colors are generally restricted to red for the rear of the vehicle, amber for the sides of the vehicle, and white for the front of the vehicle.
Many operators choose to display a design or pattern of lights on their vehicle for decorative purposes, for advertising, or for increased safety. For example, a motorcyclist may want to increase their visibility to other operators by attaching additional lighting to the front, back, or sides of the motorcycle. Alternatively, an operator may desire to have accessory lighting on their vehicle for show, such as a pattern that represents the logo and colors of their favorite sports team. However, as mentioned above, the D.O.T. limits the colors of lights that may be used while a vehicle is in operation on public roadways. The decorative value, color variation, and level of customization are limited by the D.O.T. color restrictions.
Currently, some lighting fixtures for vehicles utilize LEDs arranged in housings and configured to emit fixed line-of-sight designs or patterns of light. Often the LEDs are arranged in the shape of the desired pattern, which is viewable from a fixed line of sight. These fixed colors and fixed shape arrangements also have limited customization because of the above-described D.O.T. color restrictions.
FIG. 1 is an exemplary pattern 10 of LEDs 12 fixed into a Maltese cross. The LEDs 12 are arranged in the pattern 10 on a base 14. In order to change the pattern 10 or the colors of the LEDs 12, the operator must change the entire light assembly by detaching the base 14 from the vehicle.
Operators have also used LEDs for indirect lighting on motor vehicles, often called “street glow.” The LEDs used for indirect lighting do not display a pattern of light, but instead are directed toward the ground or other parts of the vehicle in order to provide a glowing effect. The fixed LEDs of FIG. 1 and the street glow lighting is available in single color LEDs and in LEDs capable of producing multiple, selectable colors.
The use of single color LEDs limits the degree to which the operator can customize and later change the color of emitted light. Single color LEDs are simple to use as they do not require the operator to set the color of the light. However, if the operator wishes to change the color of single color LED lights, they must physically replace each LED with a new LED of the desired color. Single color LEDs can display only one color, so the operator is not able to have the lights cycle between two selected colors. Single color LEDs are generally only available in several hues of each of the colors from the group of primary and secondary colors including red, green, blue, white, purple, amber, orange, sky blue, teal, and pink. It is generally not feasible for manufacturers or suppliers to make and stock many subtle variations of hues, such as reddish purple or bluish purple.
FIG. 2 illustrates how each individual LED produces a small, intense area of light in a conical pattern when projected towards a lens 18 that forms a backlit surface. When viewed in direct line of sight, such as the pattern 10 in FIG. 1, the array of LEDs 12 form a non-uniform light source because each LED 12 is discernable. More particularly, each LED 12 produces a visual optical “hotspot” in the light pattern. The severity of the hotspot is intensified by the distance between a back 16 of the base 14 and the lens 18. The smaller the distance between the back 16 and the lens 18, the more intense the hotspot, and a less uniform pattern of light will be due to gaps between the cones of light.
The ability to discern the details of a shape or pattern of light is directly related to the uniformity across the viewable area of the illumination used to create the emitted pattern. Greater pattern detail can be discerned if the light emitted is more uniform. Thus, while a line-of-sight, fixed-LED approach may maximize brightness, the patterns of lights emitted are limited to rudimentary designs and patterns.
FIG. 3 illustrates a larger distance between the back 16 of the base 14 and the lens 18. The greater distance allows the light emitted from the LEDs 12 to be more uniform and therefore create the illuminated pattern with fewer hotspots. By allowing sufficient distance between the LEDs 12 and the lens 18, i.e., the backlit surface, the light is allowed to diffuse through the lens 18. The beams of light overlap before striking the diffusing lens 18 and create a more uniform illumination. However, the distance between the back 16 and the lens 18 must be minimized for motor vehicle applications.
In order to use LEDs capable of emitting multiple, selectable colors, a color changing control device is used to control an amount of electrical flow to each of a respective red, green, and blue emitter. The various colors are created by mixing combinations of red, green, and blue. The current motor vehicle LED color control devices can cycle between multiple colors, but the patterns of colors and the colors emitted are preset by the manufacturer. The operator cannot select the colors they want and often results in undesired colors being displayed. Thus, the operator is not able to customize the colors in the cycle to match vehicle paint colors, company colors, product advertising colors, favorite sports teams, or to celebrate a holiday.
Prior motor vehicle light control devices could only be configured to emit light in a fashion so as to emulate single color LEDs. To set multicolor LEDs to a given color, the lights must be manually stopped on the desired color as they are cycling through the range of colors the LEDs can produce. Alternatively, the operator sets the light emitted by the light sources separately through a non-indexed interface to achieve a desired color or color mix. This process is repeated each time the operator desires to change colors.
Equipping a fleet of vehicles with an illuminated design of a company logo is difficult because each vehicle should have the same color or mix of color light emitted. The company may want to change the color if delivering a certain product in order to advertise the product, or the company may desire to change the colors for a holiday. With current control schemes it is difficult to achieve consistency in the control of the color across their fleet of vehicles.
In addition, it is time-consuming to set the amount of light emitted by the multicolor light sources of each vehicle in the fleet to achieve the desired hue not only initially, but whenever a new color is to be displayed. It is also difficult to get a color consistently repeated across each vehicle in the fleet, as manually setting the color mix visually is subject to variations in the settings when the process is repeated numerous times. This problem is compounded when the vehicles are geographically separated so that using one as a visual reference for another is not possible.